The invention relates to the harvesting of produce from large farms and particularly to harvesting of very high quality produce often referred to as market fresh produce. While the invention will be described in terms of the harvesting of tomatoes and has particular application to the harvesting of market fresh tomatoes, it will be understood that the invention also has application to various other types of produce. Market fresh tomatoes are currently hand picked during daylight hours. Attempts to fully mechanize the harvesting of market fresh tomatoes have been largely abandoned because such prior art apparatus result in excessive damage to the tomatoes. Those skilled in the art will recognize that harvesting of market fresh tomatoes is much more demanding than harvesting of tomatoes which are to be canned. Tomatoes intended for canning need not be handled as gently as market fresh tomatoes because damage to the tomatoes will not be visible on the canned product.
Up until the early 1970s tomato harvesting was strictly a manual operation. Field workers walked along the rows, picked the tomatoes and placed the picked tomatoes in buckets. These in turn would be loaded on a traveling storage trailer.
The problems with using strictly manual labor include: high labor costs, difficult work, and hazardous working conditions. The latter includes working in the sun, breathing dust, walking uneven dirt rows, bending, lifting, turning, twisting, stretching, carrying heavy buckets, and working around dangerous equipment. The workers are usually limited to working during daylight hours. This leads to high manual labor costs, injury to workers and high cost for hand picked tomatoes.
Subsequently, a number of mechanical tomato harvesting machines were developed. These all had one common goal, that is, eliminate the need for the worker. Machine harvesting of fresh market tomatoes has been tried in the past. Such machines attempted doing the whole operation. More specifically, a typical machine included mechanisms for cutting the vine, conveying the vines into the machine and then shaking the tomatoes mechanically off the vines and then conveying the tomatoes onto another conveyor and then onto a storage truck. This proved to be unsuccessful due to the bruising and damage to the tomatoes that occurs in shaking them off the vine and dropping the tomatoes onto the conveyor. This method has been discontinued. The main problem with all prior art mechanical harvesters is that, contrary to popular belief, fully automatic harvesting, does not result in a better overall job than the job produced by hand picking. The industry has been unable to develop a practical machine that can duplicate the unbelievable complex tasks of quickly visualizing each tomato, making a decision as to the value of the tomato, removing the tomato in a gentle and delicate manner and placing the tomato on a conveyor so as to avoid bruising the tomato.
Prior tomato harvesters are extremely complex, with a great number of moving and shaking parts. The shaking parts were required in an attempt to try and replace the delicate hand removal of the tomatoes. This complexity resulted in frequent mechanical equipment failures and numerous adjustments being necessary. The acquisition cost and operating cost were very high. This industry has made attempts to develop new varieties of tomatoes that can take more abuse in mechanical removal and other properties where the care and quality is not important. This practice has lead to picking tomatoes before they are ripe resulting in unappetizing tomatoes with a poor taste.
The historical approaches to harvesting of tomatoes is illustrated by a number of United States Patents that issued in the period between 1970 and 1989. Such patents included U.S. Pat. Nos. 3,986,561; 4,118,311; 4,262,477; and 4,584,826. All of these describe a chassis carried on wheels on which workers stand while sorting tomatoes. U.S. Pat. Nos. 4,426,832 and 4,727,714 describe additional aspects of the prior art apparatus. Most of these patents include shaking mechanisms to remove the tomatoes from the vines. Most cut the vines near the surface of the ground.
A primary object of this invention is to combine the best of man and machine in harvesting market fresh tomatoes. Stated another way, it is an object of the invention is to provide a machine that (1) will do that part of the harvesting task that can be accomplished by a machine without compromising the quality of the produce that is harvested and (2) will facilitate the manual accomplishment of the harvesting task that cannot be satisfactorily accomplished by a machine.
Another object of the invention is to avoid damage to the produce.
An additional object of the invention is to provide better working conditions for the personal that are required in the harvesting process and thus to ensure good productivity from this personnel.
Still another object is to facilitate harvesting the crop even if there is no sunlight.
Yet another object of the invention is to reduce overall labor costs.